Edwaed douglas



(No Model.)

B. DOUGLAS.

FOLDING SQUARE. No. 363,321. Patented Ma 17, 1887.

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EDWARD DOUGLAS, OF CINCINNATI, OHIO, ASSIGNOR OF ONE-HALF TO JOHN DOUGLAS, OF SAME PLACE.

FOLDING SQUARE.

SPECIFICATION forming part of Letters Patent No. 363,321, dated May 17, 1887. Application filed October 11, 1886. Serial No. 215,877. (No model.)

To all whom it may concern.-

Be it known that I, EDWARD DOUGLAS,2L citizen of the United States. residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Squares, of which the following is a specification.

My invention relates more particularly to steel squares principally used by carpenters and other artificers, whereby the implement can be folded to strike a desired angle or entirely closed up, so that it can be stewed away in the tool-box without taking up unnecessary room or requiring a special place for that purpose.

As the implements are now made the arms are rigid, being cut out of one piece of metal, and when placed in the ordinary small toolbox, which the mechanic carries with him, one of these arms will project and be constantly in the way; and, as before stated, one of the objects of my invention is to remedy this objection.

The features ofmyimprovements will be fully understood from the description hereinafter and the accompanying drawings, of my specification, in which Figure 1 is a View of the square folded up. Fig. 2 is a view of the square in its ordinary posi tion-th at is, with the arms at right angles to each other. Fig. 3 is a view showing one of the arms partially folded at an intermediate angle. Fig. at is a section taken through one of the arms and shows the thumb-wedge whereby the arms are held at any desired angle.

A represents one arm of the square, and B the other. At the point of unison the ends of these arms are mitered, the angle of the miter out being such that when the arms are extended to their utmost limit they will be at right angles to each other. These arms are joined one forming part to the other by means of the arcs or segments G D, the former being rigidly attached to the arm or straight-edge- B by means of rivets or like means, while the latter is fastened to the straight-edge A. These arcs respectively move in grooves, which are cut in the faces of the straight-edges, as shown. The sides of these grooves are beveled,and correspondingly so are the sides of the arcs which work in them. By means of this beveling the arcs are held in the grooves flush with the faces of their respective 1 and 3, the ends are carried within the respective grooves. These arc-slides and their respective grooves may all be on one side of the square, as shown; or they may be placed alternately on opposite sides, if desired.

In order to hold the arms at any given angle I employ a thumb-screw, T, working in a socket, s. This screw has attached to it at one end a Wedge-shaped piece, which is intended to bear against the segmental slide when it is intended to hold it at any desired angle. By operating the thumb-piece of the screw the segmentslides are fastened or released. The thumb-piece may project out beyond the faces of the arm, as seen in Fig. 4; or the arm may be dished or hollowed out, as seen in Figs. 2 and 3, and the thumb-piece set in,so that it will not rise beyond the arms surface.

The segment-slide C may be divided off into the various degrees of angles, as in an ordinary protractor, permitting the arms A and B to be adjusted so as to indicate the same.

From the foregoing description, coupled with reference to the drawings, it will be seen that I have produced a square which can be made of two pieces of metal, instead of requiring it to be stamped or cut out of one, that it requires less room when stowed away than those now in use, and that in itself it can be utilized for projecting the different angles required, which cannot be done by the metallic squares now employed.

I have shown and described two or moresegments, with their corresponding grooves; but I desire it understood that I do not limit myself to that number, as I may use more or less with out impairing the efliciency of my instrument. To illustrate: I may have a single segment attached to one of the arms, which will operate in a corresponding groove on the other arm, and this for all practical purposes will answer just as well as if two or more segment-links and theirgrooves were provided; also,I have shown the segments attached alternately to each of the arms. In point of fact this is not essential, for the segments may all be a part of one arm, the other arm containing the grooves for their reception.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a square, one or more segmental links attached to one arm and operating in corresponding grooves on the other arm, the sides of the segments and grooves being beveled, so as to prevent disengagement, substantially as shown and described, and for the purposes specified.

I 2. The arm A, provided with segment-slide D and segment-slot E, in combination with arm B, with its affixed slide 0 and slot F, whereby the arms are connected together and theimplement used as a square, or to indicate any desired angle, substantially as shown and described.

3. In asqnare, the arms A B, beveled so'as to 25 form a right or any other desired ang1e,and connected by one or more sliding arcs operating in corresponding grooves on the opposite arm,the arcs being provided with the angular degrees, and having their sides beveled, so as to bear 30 against the interior of said grooves, substantially as shown and described, and for the purposes specified. V

4, The Wedge e, operated by the thumb-screw T,in combination with one of the straight-edges 5 and the segments, whereby the latter are held or released, substantially as shown and described.

EDWARD DOUGLAS. \Vitnesses:

W. ELLwooD WYNNE, J OHN DOUGLAS. 

